DC-to-DC converters are common components that take a first input voltage and convert it into one or more output voltages. This allows a user to take a higher battery voltage, such as 48 volts, and convert it down to a first and second output voltage, such as 12 volts and 5 volts, enabling the higher voltage DC source to be used to power various circuits that require lower voltage. Such a converter can provide either a single output voltage or multiple voltage outputs. DC-DC power converters typically comprise one of three configurations.
The first configuration is a single FR-4 Printed Wiring Board (PWB) with parts on both sides, with or without encapsulation. Flame Resistant 4 (FR-4) is a form of epoxy resin bonded glass fabric (ERBGF). The main limitation of this configuration is the limited available board areas for mounting components. Furthermore, it does not provide thermal isolation of sensitive components and is subject to noise from the power elements. Furthermore, components often have to be shrunk to fit the available footprint, which reduces the upper power range, e.g., ˜50 W for a 1″×1″ footprint.
The second configuration comprises one Insulated Metal Substrate (IMS) board with parts on one side and optional heat sink on the other flat side, plus one FR-4 PWB with parts on both sides and interconnects to the IMS board. While this configuration offers more areas for mounting components, the outward facing surface of the IMS is not populated with components.
The third configuration typically seen with DC-DC power converters comprises multiple FR-4 PWBs with parts on each PWB. However, the “daughter” boards are not parallel to the main board, which can interfere with airflow over the components depending on the orientation of the power converter.
Many current designs also have many interconnects between the boards, which reduces the board area available for mounting components.